Surface treatment per qq-p-416, type 1, class 3 for top plate only; manganese phosphate, type m, or zinc phosphate, type z, per mil-p-16232, class 1, except for top plate; top plate=aisi 01, hardness rc26-32; bolt carrier=8620, cold drawn stress relieved steel, brinel hardness 217-229; bolt= carpentersteel 158, brinel hardness 195-235; ejector pin=titanium; locating pin=aisi 01, hardness rc26-32
An item consisting of a bolt carrier, a breech bolt, a top plate, and a locating pin. It replaces a breech bolt in a rifle or machine gun to alter the operation of the weapon from gas to blow-back so that low-powered practice ammunition may be used. It is not intended for non-practice usage. Excludes bolt, breech and breechblock.
Classification: Parts and accessories for military rifles of heading 9301
NSN 6620-00-226-2285
NSN 6610-00-382-0266
NSN 5895-01-161-1706
NSN 5990-01-517-7848
NSN 6110-00-799-7668
NSN 6240-00-361-1421
NSN 5935-01-265-1111
NSN 6620-00-234-8918
NSN 5998-01-571-3293
NSN 6650-01-199-4968
NSN 5855-00-058-1293
NSN 5855-01-612-1834